This invention relates to a dual sash window assembly or to a window assembly in which a pair of sashes are mounted in parallel, closely spaced planes within a supporting frame for relative horizontal sliding or rolling movement. The invention has particular reference to weathertight sealing means in the dual sash window assembly of the type defined.
The weathertight sealing of window assemblies have been proposed in various forms. However, while windows having only one movable sash can admittedly be sealed relatively easily, it has been considered difficult to seal, in a truly simple and inexpensive manner, windows in which a pair of sashes are both movable relative to each other and to the supporting frame.